Technical Field
The invention relates to seating structures and, more particularly, to seating structures that include a suspension diaphragm for receiving an occupant's weight.
Discussion of Art
Aircraft seats commonly have a back structure and a seat bottom structure that are fitted with cushions and upholstery. The seat bottom carries the majority of the passenger's weight and is therefore of particular concern with regard to comfort. The seat bottom is located above structural members of the seat frame specifically the beam elements. To support the passenger above the hard, uneven seat structure, the seat bottom portion of the seat often employs either an elastomeric fabric diaphragm or a rigid pan that is covered with cushioning. Each method provides certain comfort benefits but neither is without shortcomings.
Rigid pans provide a consistent platform for the passenger and can have contoured shapes that address ergonomic needs. However, they are hard and require thicker cushions to make the occupant comfortable. Thicker cushions reduce the passenger's living space and increase weight.
Diaphragm systems typically comprise a fabric suspension tensioned across a frame. A cushion is placed on top of the diaphragm to distribute loads and pad areas where the frame might be felt by the passenger. Being flexible, the diaphragm has inherent comfort advantages. However, even if tightly tensioned, the diaphragm is often deflected by the passenger enough to cause contact with structural parts of the seat such as the beam. This contact is often felt by the passenger, causing discomfort. As with rigid pans, the correction is too often a thicker, heavier cushion. At a time when space is valuable to the passenger and weight means higher costs to the airline, thicker cushions are undesirable.